I only know what I can conclude from my experience. And my experience is limited to simulations of overunity circuitry.

What I conclude is this...
Thanks go to Franco Bruno Cortelleti for pointing out how important this knowledge is by designating an entire space on Quora for its discussion...

https://www.youtube.com/watch?v=xIRzYfbl5lU&t=320s

What I get out of what Eric is saying is that there is applied voltage, then there is inductive reactance which gives us back EMF, then there is ionic movement (such as: the movement inside of the electrolyte of batteries, or the movement within weather patterns and storm fronts, or the ionization inside of a spark gap which is preparing to fire, but hasn't begun to form an arc, yet), and lastly there is capacitive reactance.

He calls the electrostatic potential what I call applied voltage. Eric calls the electromotive force what I call inductive reactance. And Eric calls conduction current what I call ionic movement. And lastly, he calls displacement current what I call capacitive reactance.

These, then, are the four quadrants of electricity according to how Eric codifies them and how I would try to translate them back into the electrical engineering world of vocabulary which I have filtered to focus on just what pertains to how electronic simulators are designed to operate within the confines of their software.

Applied voltage is the first "V" of Ohm's Law. Back EMF is a magnetic phenomenon related to coils. So, this is why I choose to qualify this with inductive reactance. It is the current which coils are notorious for exhibiting. But it is this current which is faked by a slight-of-hand trickery in which voltage is divided by resistance over time to fake this current. This is why Eric puts this in the same category as where he puts the electrostatic potential since both the electrostatic potential and the electromotive force are two types of voltage (neither of them are current). And this is why I would agree with him by calling this fake current, which should be renamed: voltage divided by resistance, which gets multiplied against applied voltage (called: the electrostatic potential) to get power in Ohm's Law, ie. voltage squared divided by resistance equals power.

But if we substitute capacitive reactance in place of inductive reactance, and keep applied voltage (the electrostatic potential), then we get what I like to call: Mho's Law in which resistance is divided by voltage squared and then the whole thing is negated to give us overunity, in the form of the generation (ie, synthesis) of electricity, inside of this type of circuitry.

So, an overunity circuit replaces the electromotive force with displacement current. In other words, a fake current (born of magnetism and Michael Faraday's Law of Induction) is replaced with true current born of dielectric behavior.

The waveforms of inductive reactance are the sine waves we have become accustomed to. Conversely, the waveforms of capacitive reactance are triangular waves, or spikes in their most severe manifestation.

Correct me if I'm wrong; but, this is what I glean from all of this...